Loans and Allowance for Credit Losses (Details 4) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 216,088	$ 209,835
Total outstanding commitments	439,375	423,565
Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	61,534	56,648
Commercial Real Estate Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	36,557	35,851
Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	39,920	37,082
Credit Card [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	16,905	17,360
Other Retail [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	48,035	48,107
Total Loans, Excluding Covered Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	202,951	195,048
Covered Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	13,137	14,787
Pass Internal Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	207,017	199,091
Total outstanding commitments	428,038	410,457
Pass Internal Credit Rating [Member] | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	59,131	54,003
Pass Internal Credit Rating [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	32,587	30,733
Pass Internal Credit Rating [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	38,725	35,814
Pass Internal Credit Rating [Member] | Credit Card [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	16,518	16,910
Pass Internal Credit Rating [Member] | Other Retail [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	47,618	47,665
Pass Internal Credit Rating [Member] | Total Loans, Excluding Covered Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	194,579	185,125
Pass Internal Credit Rating [Member] | Covered Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	12,438	13,966
Special Mention Criticized Internal Credit Rating [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,084	2,070
Total outstanding commitments	3,473	3,418
Special Mention Criticized Internal Credit Rating [Member] | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,142	1,047
Special Mention Criticized Internal Credit Rating [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	756	793
Special Mention Criticized Internal Credit Rating [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	20	19
Special Mention Criticized Internal Credit Rating [Member] | Other Retail [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	37	24
Special Mention Criticized Internal Credit Rating [Member] | Total Loans, Excluding Covered Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,955	1,883
Special Mention Criticized Internal Credit Rating [Member] | Covered Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	129	187
Classified Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,987	8,674
Total outstanding commitments	7,864	9,690
Classified Criticized [Member] | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,261	1,598
Classified Criticized [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,214	4,325
Classified Criticized [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,175	1,249
Classified Criticized [Member] | Credit Card [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	387	450
Classified Criticized [Member] | Other Retail [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	380	418
Classified Criticized [Member] | Total Loans, Excluding Covered Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,417	8,040
Classified Criticized [Member] | Covered Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	570	634
Total Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	9,071	10,744
Total outstanding commitments	11,337	13,108
Total Criticized [Member] | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,403	2,645
Total Criticized [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,970	5,118
Total Criticized [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,195	1,268
Total Criticized [Member] | Credit Card [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	387	450
Total Criticized [Member] | Other Retail [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	417	442
Total Criticized [Member] | Total Loans, Excluding Covered Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,372	9,923
Total Criticized [Member] | Covered Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 699	$ 821